My fan from the time my key is in the on position until the time i take the key out and about 10 minutes after my car is off runs in the high speed mode.... it is killing my battery and i do not know if it is my temp sensor or is my fan relay or something differant. my car temp gauge reads the normal temperature even when my car is cool. it always stays at around 180..... i need some help

 

I would replace the temp sensor and thermostat.